Radiology: Normal Chest X-Rays

X-rays are the oldest and most popular form of radiology imaging, and automated interpretation of chest x-rays is a a fun machine learning task. In this post, I’ll introduce the basics of chest x-ray interpretation.

Every year medical personnel perform 3.6 billion medical procedures involving ionizing radiation. A large number of these procedures are projectional x-rays (commonly just called “x-rays”), where a very small dose of radiation is used to create a 2-D pictures of the chest, abdomen, pelvis, or limbs.

Chest x-rays in particular can be used to identify a variety of findings, including pneumonia, pneumothorax (air pockets inside the chest), heart failure, rib fractures, lung masses, big lymph nodes, effusions (extra fluid in the chest), and hernias through the diaphragm, among other conditions. But in order to understand what these abnormal findings look like on a chest x-ray, it’s important to first learn what a healthy chest x-ray looks like.

Check out “ Anatomy for Radiology: Chest “ for a review of basic chest anatomy.

Chest X-Ray Coloration

Normal Chest X-Ray. This image shows a normal chest. Darker colors indicate less dense material, and lighter colors indicate more dense material. The lungs appear black because they are spongy with a lot of air content. The bones appear…